CVE-2026-35089
CVE-2026-35089 is a high-severity vulnerability with a CVSS 4.0 base score of 8.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1391.
Key facts
- Severity: High (CVSS 4.0 base score 8.7)
- EPSS exploit prediction: 1% (44th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-32277
- Weakness: CWE-1391
- Published:
- Last modified:
Description
In Slican telephone exchanges secure key is generated in a predictable manner using properties of the telephone exchange which can be obtained without authentication. An unauthenticated attacker can deduce the secure key and obtain admin credentials. This issue was fixed in versions below: - IPx series: version 6.61.0040 - CCT-1668: version 6.56.0430 - MAC-6400: version 6.56.0430 - CXS-0424: version 6.30.0510 The issue STILL EXISTS in End-Of-Life telephone exchanges in versions 4.xx and below: - CCT-1668 (CCT1CPU) - MAC-6400 - CXS-0424 These products were discontinued in 2011 and 2012 and and will not receive updates. These products require a hardware update in order to receive a software update. The vendor recommends that users of these devices contact the their service department directly to determine the options for upgrading.
Frequently asked questions
- What is CVE-2026-35089?
- In Slican telephone exchanges secure key is generated in a predictable manner using properties of the telephone exchange which can be obtained without authentication. An unauthenticated attacker can deduce the secure key and obtain admin credentials. This issue was fixed in versions below: - IPx series: version 6.61.0040 - CCT-1668: version 6.56.0430 - MAC-6400: version 6.56.0430 - CXS-0424: version 6.30.0510 The issue STILL EXISTS in End-Of-Life telephone exchanges in versions 4.xx and below: - CCT-1668 (CCT1CPU) - MAC-6400 - CXS-0424 These products were discontinued in 2011 and 2012 and and will not receive updates. These products require a hardware update in order to receive a software update. The vendor recommends that users of these devices contact the their service department directly to determine the options for upgrading.
- How severe is CVE-2026-35089?
- CVE-2026-35089 has a CVSS 4.0 base score of 8.7, rated high severity.
- Is CVE-2026-35089 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-35089?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-35089 have an EU (EUVD) identifier?
- Yes. CVE-2026-35089 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32277.
- When was CVE-2026-35089 published?
- CVE-2026-35089 was published on 2026-05-27 and last updated on 2026-06-17.
References
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